ATI RN
Microbiology A Systems Approach Test Bank Questions
Question 1 of 5
A 49-year-old countryman got an itching papule on the dorsum of his right hand. In the centre there is a vesicle with serosanginous exudate. Within the next 2 days the patient developed a painless edema of hand and forearm. On the 4th day the temperature rose to 38,5oC, in the right axillary region a large painful lymph node was found. One daybefore the onset of the disease the patient had examined a dead calf. What is the most likely diagnosis?
Correct Answer: D
Rationale: The most likely diagnosis is D: Lymphocutaneous tularemia. The key clues include exposure to a dead animal, vesicle with serosanginous exudate, painless edema progressing to lymph node involvement, and fever. Tularemia is caused by Francisella tularensis, commonly acquired through contact with infected animals. The characteristic ulcer at the site of entry, lymphadenopathy, and systemic symptoms point towards tularemia. Cutaneous anthrax (A) presents with a painless ulcer and black eschar. Bubonic plague (B) typically presents with buboes (swollen lymph nodes) and fever. Carbuncle (C) is a deep skin infection typically caused by Staphylococcus aureus.
Question 2 of 5
A bacteriological laboratory has been investigating a sample of homemade dried fish that was the cause of severe food poisoning. Microscopy of the culture inoculated in Kitt-Tarozzi medium revealed microorganisms resembling a tennis racket. What diagnosis can be made?
Correct Answer: A
Rationale: The correct answer is A: Botulism. The tennis racket appearance seen under the microscope is characteristic of Clostridium botulinum, the bacterium responsible for botulism. This bacterium produces spores that resemble a tennis racket shape. Botulism is a type of food poisoning caused by the ingestion of the toxin produced by Clostridium botulinum. Summary: B: Salmonellosis is caused by Salmonella bacteria, which do not exhibit a tennis racket appearance. C: Cholera is caused by Vibrio cholerae, which also does not resemble a tennis racket under the microscope. D: Dysentery is typically caused by bacteria such as Shigella or Entamoeba histolytica, neither of which exhibit the characteristic tennis racket appearance.
Question 3 of 5
The following spore-forming bacteria can be preserved in soil over a long period of time: clostridia of tetanus, botulism, anaerobic gas infection. Name the way with which these microorganisms get into soil.
Correct Answer: A
Rationale: Step 1: Clostridia of tetanus, botulism, anaerobic gas infection are spore-forming bacteria. Step 2: Spores are resistant structures that allow bacteria to survive in harsh conditions. Step 3: Feces contain these spore-forming bacteria due to contamination. Step 4: When feces are deposited on soil, the spores of these bacteria enter the soil. Step 5: Spores can remain dormant in soil for long periods. Summary: Choice A is correct as spore-forming bacteria enter soil through feces, which act as a source of contamination. Choices B, C, and D are incorrect as they do not involve the direct introduction of spores into soil like feces do.
Question 4 of 5
A patient who suffered form syphilis took a course of antibiotic therapy and fully recovered. Some time later he was infected again with Treponema pallidum. What form of infection is it?
Correct Answer: A
Rationale: The correct answer is A: Reinfection. This is because the patient fully recovered from the initial syphilis infection after antibiotic therapy, indicating the elimination of the pathogen. Subsequently getting infected again with Treponema pallidum suggests a new exposure to the same pathogen, resulting in a new infection. Recurrence (B) would imply the reactivation of the same infection, which is not the case here. Superinfection (C) refers to a new infection that occurs on top of an existing infection, which is not the scenario described. Secondary infection (D) typically refers to an infection that occurs after an initial infection weakens the immune system, which is not the case in this scenario.
Question 5 of 5
When doctors of a sanitary and epidemiologic institution examine employees of public catering establishments they often reveal asymptomatic parasitosis, that is when a healthy person is a carrier of cysts that infect other people. What causative agent can parasitize in such a way?
Correct Answer: A
Rationale: The correct answer is A: Dysenteric amoeba. This is because dysenteric amoebas can cause asymptomatic parasitosis, where a healthy person carries cysts that can infect others. Dysenteric amoebas are known to infect the intestines and can be transmitted through contaminated food or water. Choice B, Malarial plasmodium, causes malaria transmitted through mosquitoes. Choice C, Enteral trichomonad, causes diarrhea and is transmitted through contaminated water. Choice D, Dermatotropic leishmania, causes skin lesions and is transmitted through sandfly bites. These choices do not fit the scenario of asymptomatic parasitosis in public catering establishments.